Finding the Fourth Proportional to 420.99, 631.78 and 235.70
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Solution
The fourth proportional to 420.99, 631.78 and 235.70 is: 353.72
Step by Step Solution
- Step 1: Write the proportion equation
420.99 : 631.78 = 235.70 : x - Step 2: Convert to fraction form
420.99/631.78 = 235.70/x - Step 3: Cross multiply
420.99x = 631.78 × 235.70 - Step 4: Simplify right side
420.99x = 148,910.55 - Step 5: Solve for x
x = 148,910.55/420.99 - Step 6: Final answer
x = 353.72
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.